This is a follow-up of https://go-review.googlesource.com/#/c/20653/

Special case computation for slices with elements of byte size or
pointer size.

name                      old time/op  new time/op  delta
GrowSliceBytes-4          86.2ns ± 3%  75.4ns ± 2%  -12.50%  (p=0.000 n=20+20)
GrowSliceInts-4            161ns ± 3%   136ns ± 3%  -15.59%  (p=0.000 n=19+19)
GrowSlicePtr-4             239ns ± 2%   233ns ± 2%   -2.52%  (p=0.000 n=20+20)
GrowSliceStruct24Bytes-4   258ns ± 3%   256ns ± 3%     ~     (p=0.134 n=20+20)

Change-Id: Ice5fa648058fe9d7fa89dee97ca359966f671128
Reviewed-on: https://go-review.googlesource.com/21101Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The exec wrapper lock file was opened, locked and then never used
again, assuming it would close and unlock at process exit.
However, the garbage collector could collect and run the *os.File
finalizer that closes the file prematurely, rendering the lock
ineffective.

Make the lock global so that the lock is live during the entire
execution.

(Hopefully) fix the iOS builders.

Change-Id: I62429e92042a0a49c4f1ea553fdb32b6ea53a43e
Reviewed-on: https://go-review.googlesource.com/21137Reviewed-by: David Crawshaw <crawshaw@golang.org>

When creating binaries for dynamic linking, the linker moves
read-only data symbols that contain pointers into relro sections.
It is not setup for handling a go.string symbol moving to relro.

Instead of teaching it how (because go.string symbols with pointers
are unusual anyhow), put the data in a type.. section.

Fixes the android builder.

Change-Id: Ica4722d32241643c060923517b90276ff8ac6b07
Reviewed-on: https://go-review.googlesource.com/21110Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Passes toolstash -cmp.

name       old alloc/op    new alloc/op    delta
Template      58.5MB ± 0%     57.8MB ± 0%  -1.15%        (p=0.000 n=10+10)
Unicode       41.3MB ± 0%     41.2MB ± 0%  -0.17%        (p=0.000 n=10+10)
GoTypes        196MB ± 0%      193MB ± 0%  -1.26%        (p=0.000 n=10+10)
Compiler       863MB ± 0%      850MB ± 0%  -1.49%        (p=0.000 n=10+10)

name       old allocs/op   new allocs/op   delta
Template        522k ± 0%       507k ± 0%  -2.99%        (p=0.000 n=10+10)
Unicode         403k ± 0%       401k ± 0%  -0.42%        (p=0.000 n=10+10)
GoTypes        1.58M ± 0%      1.52M ± 0%  -3.61%        (p=0.000 n=10+10)
Compiler       6.47M ± 0%      6.17M ± 0%  -4.62%        (p=0.000 n=10+10)

Change-Id: Ia7a6242e8d226b41966c344d253814dcce6424a8
Reviewed-on: https://go-review.googlesource.com/21141
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

There's a race between runtime.goexitsall killing all OS processes
of a go program in order to exit, and runtime.newosproc forking a
new one.  If the new process has been created but not yet stored
its pid in m.procid, it will not be killed by goexitsall and
deadlock results.

This CL prevents the race by making the newly forked process
check whether the program is exiting.  It also prevents a
potential "shoot-out" if multiple goroutines call Exit at
the same time, which could possibly lead to two processes
killing each other and leaving the rest deadlocked.

Change-Id: I3170b4a62d2461f6b029b3d6aad70373714ed53e
Reviewed-on: https://go-review.googlesource.com/21135
Run-TryBot: David du Colombier <0intro@gmail.com>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David du Colombier <0intro@gmail.com>

During random stealing we steal 4*GOMAXPROCS times from random procs.
One would expect that most of the time we check all procs this way,
but due to low quality PRNG we actually miss procs with frightening
probability. Below are modelling experiment results for 1e6 tries:

GOMAXPROCS = 2 : missed 1 procs 7944 times

GOMAXPROCS = 3 : missed 1 procs 101620 times
GOMAXPROCS = 3 : missed 2 procs 3571 times

GOMAXPROCS = 4 : missed 1 procs 63916 times
GOMAXPROCS = 4 : missed 2 procs 61 times
GOMAXPROCS = 4 : missed 3 procs 16 times

GOMAXPROCS = 5 : missed 1 procs 133136 times
GOMAXPROCS = 5 : missed 2 procs 1025 times
GOMAXPROCS = 5 : missed 3 procs 101 times
GOMAXPROCS = 5 : missed 4 procs 15 times

GOMAXPROCS = 8 : missed 1 procs 151765 times
GOMAXPROCS = 8 : missed 2 procs 5057 times
GOMAXPROCS = 8 : missed 3 procs 1726 times
GOMAXPROCS = 8 : missed 4 procs 68 times

GOMAXPROCS = 12 : missed 1 procs 199081 times
GOMAXPROCS = 12 : missed 2 procs 27489 times
GOMAXPROCS = 12 : missed 3 procs 3113 times
GOMAXPROCS = 12 : missed 4 procs 233 times
GOMAXPROCS = 12 : missed 5 procs 9 times

GOMAXPROCS = 16 : missed 1 procs 237477 times
GOMAXPROCS = 16 : missed 2 procs 30037 times
GOMAXPROCS = 16 : missed 3 procs 9466 times
GOMAXPROCS = 16 : missed 4 procs 1334 times
GOMAXPROCS = 16 : missed 5 procs 192 times
GOMAXPROCS = 16 : missed 6 procs 5 times
GOMAXPROCS = 16 : missed 7 procs 1 times
GOMAXPROCS = 16 : missed 8 procs 1 times

A missed proc won't lead to underutilization because we check all procs
again after dropping P. But it can lead to an unpleasant situation
when we miss a proc, drop P, check all procs, discover work, acquire P,
miss the proc again, repeat.

Improve stealing logic to cover all procs.
Also don't enter spinning mode and try to steal when there is nobody around.

Change-Id: Ibb6b122cc7fb836991bad7d0639b77c807aab4c2
Reviewed-on: https://go-review.googlesource.com/20836Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>

Fixes the iOS builders

Change-Id: I5097ca19048381ffb5a4c5ea038b7c4aa18ee4b7
Reviewed-on: https://go-review.googlesource.com/21132Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I6113145baa727b9fd103765f74dc5d7af86dfdf8
Reviewed-on: https://go-review.googlesource.com/21131
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change control flow to probe with N=1. This calls benchFunc
the same number of times as the old implementation in the
absence of subbenchmarks.

To be compatible with existing tools, benchmarking only
prints a line for "leaf" benchmarks. This means, though, that
the name of a benchmark can only be printed after the first
iteration.

Issue #14863

Change-Id: Ic7b9b89b058f8ebb5287755f24f9e47df8c9537c
Reviewed-on: https://go-review.googlesource.com/21043
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Also added go:generate directive.

Change-Id: Ib1f0eddc75e3c47a4d904786a29b964a35b18456
Reviewed-on: https://go-review.googlesource.com/21042Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>

This change removes a lot of dead code. Some of the code has never been
used, not even when it was first commited. The rest shouldn't have
survived refactors.

This change doesn't remove unused routines helpful for debugging, nor
does it remove code that's used in commented out blocks of code that are
only unused temporarily. Furthermore, unused constants weren't removed
when they were part of a set of constants from specifications.

One noteworthy omission from this CL are about 1000 lines of unused code
in cmd/fix, 700 lines of which are the typechecker, which hasn't been
used ever since the pre-Go 1 fixes have been removed. I wasn't sure if
this code should stick around for future uses of cmd/fix or be culled as
well.

Change-Id: Ib714bc7e487edc11ad23ba1c3222d1fd02e4a549
Reviewed-on: https://go-review.googlesource.com/20926Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Store already padded keys instead of storing key and padding it during
Reset and Sum. This simplifies code and makes Reset-Write-Sum sequences
faster, which helps /x/crypto/pbkdf2.

HMAC benchmark:

benchmark                    old ns/op     new ns/op     delta
BenchmarkHMACSHA256_1K-4     7669          7613          -0.73%
BenchmarkHMACSHA256_32-4     1880          1737          -7.61%

benchmark                    old MB/s     new MB/s     speedup
BenchmarkHMACSHA256_1K-4     133.52       134.50       1.01x
BenchmarkHMACSHA256_32-4     17.02        18.41        1.08x

PBKDF2 benchmark:

benchmark                       old ns/op     new ns/op     delta
BenchmarkPBKDF2HMACSHA256-4     1943196       1807699       -6.97%

Change-Id: I6697028370c226715ab477b0844951a83eb3488c
Reviewed-on: https://go-review.googlesource.com/21024
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

The Lookup method provides a way to extract a tag value, while
determining whether the tag key exists in the struct field's tag.

Fixes #14883

Change-Id: I7460cb68f0ca1aaa025935050b9e182efcb64db3
Reviewed-on: https://go-review.googlesource.com/20864Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #14937.

Change-Id: Iea11a32230d44d5a43f8aec812d25f13bce85895
Reviewed-on: https://go-review.googlesource.com/21038Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #6492.

Change-Id: Ibc633c43a6d134bb140addb59780a5758b35a5c5
Reviewed-on: https://go-review.googlesource.com/21057
Run-TryBot: Caleb Spare <cespare@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Ther darwin/arm{,64} exec wrapper now limits the number of concurrent
executions to 1, so remove the higher level parallel task limit from
the Go command.

Change-Id: Id84f65c3908305bde0452b3c8db6df8c5a8881bb
Reviewed-on: https://go-review.googlesource.com/21100Reviewed-by: David Crawshaw <crawshaw@golang.org>

I failed to rebase (and re-test) CL 21102 before submit, which meant
that two extra tests sneaked into testcarchive that still referenced
runtime.GOOS and runtime.GOARCH.

Convert the new tests.

While we're here, make sure pending tasks are flushed before running
the host tests. If not, the "##### misc/cgo/testcarchive" banner
and "PASS" won't show up in the all.bash output.

Change-Id: I41fc4ec9515f9a193fa052f7c31fac452153c897
Reviewed-on: https://go-review.googlesource.com/21106
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Create a byte encoding designed for static Go names.

It is intended to be a compact representation of a name
and optional tag data that can be turned into a Go string
without allocating, and describes whether or not it is
exported without unicode table.

The encoding is described in reflect/type.go:

// The first byte is a bit field containing:
//
//	1<<0 the name is exported
//	1<<1 tag data follows the name
//	1<<2 pkgPath *string follow the name and tag
//
// The next two bytes are the data length:
//
//	 l := uint16(data[1])<<8 | uint16(data[2])
//
// Bytes [3:3+l] are the string data.
//
// If tag data follows then bytes 3+l and 3+l+1 are the tag length,
// with the data following.
//
// If the import path follows, then ptrSize bytes at the end of
// the data form a *string. The import path is only set for concrete
// methods that are defined in a different package than their type.

Shrinks binary sizes:

	cmd/go: 164KB (1.6%)
	jujud:  1.0MB (1.5%)

For #6853.

Change-Id: I46b6591015b17936a443c9efb5009de8dfe8b609
Reviewed-on: https://go-review.googlesource.com/20968
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The c-archive test were recently converted from shell script to Go.
Unfortunately, it also lost the ability to target iOS and Android
that lack C compilers and require exec wrappers.

Compile the c-archive test for the host and run it with the target
GOOS/GOARCH environment. Change the test to rely on go env GOOS
and go env GOARCH instead of runtime.GOOS and runtime.GOARCH.

Fixes #8345

Change-Id: I290ace2f7e96b87c55d99492feb7d660140dcb32
Reviewed-on: https://go-review.googlesource.com/21102Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates #14047

Change-Id: I7e314e2c7e3e8da18ab023729740fbc9ea3f661e
Reviewed-on: https://go-review.googlesource.com/21063
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

In f the extra & 63 is redundant because SHRQ already
looks at the bottom 6 bits only. This is a trick on AMD64
to get rid of CMPQ/SBBQ/ANDQ if one knows that the shift
counter is small.

func f(x uint64, s uint) uint64 {
        return x >> (s & 63)
}

Change-Id: I4861c902168dabec9a6a14a85750246dde94fc08
Reviewed-on: https://go-review.googlesource.com/21073Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>

g used to produce CMPQ/SBBQ/ANDQ, but f didn't even though
s&15 is at most s&63.

func f(x uint64, s uint) uint64 {
        return x >> (s & 63)
}
func g(x uint64, s uint) uint64 {
        return x >> (s & 15)
}

Change-Id: Iab4a1a6e10b471dead9f1203e9d894677cf07bb2
Reviewed-on: https://go-review.googlesource.com/21048
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

The current runtime attempts to forward signals generated by non-Go
code to the original signal handler.  If it can't call the original
handler directly, it currently attempts to re-raise the signal after
resetting the handler.  In this case, the original context is lost.

This fix prevents that problem by simply returning from the go signal
handler after resetting the original handler.  It only does this when
the original handler is the system default handler, which in all cases
is known to not recover.  The signal is not reset, so it is retriggered
and the original handler takes over with the proper context.

Fixes #14899

Change-Id: Ib1c19dfa4b50d9732d7a453de3784c8141e1cbb3
Reviewed-on: https://go-review.googlesource.com/21006Reviewed-by: Ian Lance Taylor <iant@golang.org>

Android doesn't (generally) have /bin/sh.

Change-Id: I343817c342e3473d09c85155761682b5ddb043e4
Reviewed-on: https://go-review.googlesource.com/21075Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #14938.

Additionally some simplifications along the way.

Change-Id: I2c5fb7e32dcc6fab68fff36a49cb72e715756abe
Reviewed-on: https://go-review.googlesource.com/21046Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>

The iOS exec wrapper use complicated machinery to run a iOS binary
on a device.
Running several binaries concurrently doesn't work (reliably), which
can break tests running concurrently. For my setup, the
runtime:cpu124 and sync_cpu tests can't run reliably without one of them
crashing.

Add a file lock to the exec wrapper to serialize execution.

Fixes #14318 (for me)

Change-Id: I023610e014b327f8d66f1d2fd2e54dd0e56f2be0
Reviewed-on: https://go-review.googlesource.com/21074Reviewed-by: David Crawshaw <crawshaw@golang.org>

We were allocating a Nodes for common method calls
that did not modify the Nodes.
Though there is no clear wall time impact,
this significantly reduces the number of allocations,
so it seems worth doing.

Passes toolstash -cmp.

name       old alloc/op    new alloc/op    delta
Template      59.0MB ± 0%     58.6MB ± 0%   -0.81%        (p=0.000 n=25+25)
Unicode       41.4MB ± 0%     41.3MB ± 0%   -0.18%        (p=0.000 n=25+25)
GoTypes        198MB ± 0%      197MB ± 0%   -0.80%        (p=0.000 n=24+25)
Compiler       875MB ± 0%      865MB ± 0%   -1.09%        (p=0.000 n=25+25)

name       old allocs/op   new allocs/op   delta
Template        581k ± 0%       520k ± 0%  -10.42%        (p=0.000 n=25+25)
Unicode         413k ± 0%       403k ± 0%   -2.30%        (p=0.000 n=25+25)
GoTypes        1.78M ± 0%      1.58M ± 0%  -11.18%        (p=0.000 n=25+25)
Compiler       7.66M ± 0%      6.47M ± 0%  -15.51%        (p=0.000 n=25+25)

Change-Id: I012a9f4b333821bdf61b4f2bdff4ce5c3b5d3057
Reviewed-on: https://go-review.googlesource.com/21056Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

CL 20892 converted the misc/cgo/testcarchive test to Go.
Unfortunately, dist does not (yet) support tests running off the host
so the testcarchive is disabled for now.

For #14318

Change-Id: Iab3d0a7b5309187a603b48f22a7fa736f089f89d
Reviewed-on: https://go-review.googlesource.com/21070Reviewed-by: David Crawshaw <crawshaw@golang.org>

A retry mechanism is in place to combat the inherent flakiness of
launching iOS test binaries. Before it covered just the starting of
lldb; expand it to cover the setup steps as well. Note that the
running of the binary itself is (still) not retried, to avoid
covering over genuine bugs.

On my test device (iPhone 5S, iOS 9.3) starting lldb can take longer
than 10 seconds, so increase the timeout for that.
Furthermore, some basic steps such as setting breakpoints in lldb
can take longer than the 1 second timeout. Increase that timeout
as well, to 2 seconds.

Finally, improve the error message for when ios-deploy is not
installed.

For #14318

Change-Id: Iba41d1bd9d023575b9454cb577b08f8cae081c2a
Reviewed-on: https://go-review.googlesource.com/21072Reviewed-by: David Crawshaw <crawshaw@golang.org>

Instruct lldb to pass through SIGCONT unhindered when running iOS
tests. Fixes the TestSIGCONT test in os/signal.

For #14318

Change-Id: I669264208cc3d6ecae9fbc8790e0b753a93a5e04
Reviewed-on: https://go-review.googlesource.com/21071Reviewed-by: David Crawshaw <crawshaw@golang.org>

For darwin/arm{,64} a non-Go thread is created to convert
EXC_BAD_ACCESS to panics. However, the Go signal handler refuse to
handle signals that would otherwise be ignored if they arrive at
non-Go threads.

Block all (posix) signals to that thread, making sure that
no unexpected signals arrive to it. At least one test, TestStop in
os/signal, depends on signals not arriving on any non-Go threads.

For #14318

Change-Id: I901467fb53bdadb0d03b0f1a537116c7f4754423
Reviewed-on: https://go-review.googlesource.com/21047Reviewed-by: David Crawshaw <crawshaw@golang.org>

Some minor scoping cleanups found by a very old version of grind.

Change-Id: I1d373817586445fc87e38305929097b652696fdd
Reviewed-on: https://go-review.googlesource.com/21064
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Ignore superfluous trailing IDAT chunks which were not consumed when decoding
the image. This change fixes decoding of valid images in which a zero-length
IDAT chunk appears after the actual image data. It also prevents decoding of
trailing garbage IDAT chunks or maliciously embedded additional images.

Fixes #14936

Change-Id: I8c76cfa9a03496d9576f72bed2db109271f97c5e
Reviewed-on: https://go-review.googlesource.com/21045Reviewed-by: Nigel Tao <nigeltao@golang.org>

If name is /dev/{stdin,stdout,stderr}, return fileInfo.

Fixes #14853.

Change-Id: Ibf7d1ae7b9f3dc43f6ed7c905ea2c5102e1971cc
Reviewed-on: https://go-review.googlesource.com/20845Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Fixes #13996

Change-Id: I9b2c7fba0705900aca9a70bc6a2687667a9a976c
Reviewed-on: https://go-review.googlesource.com/20128Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Remove almost all the remaining Nod(OXXX, ... ) uses. The performance
change is due entirely to the changes to func temp(*Type). The other
cleanups have no effect, as expected.

I'll address the remaining Nod(OXXX, ...) uses in a followup CL as they
are very sensitive to change.

lucky(~/go/src/cmd/compile) % benchstat /tmp/{old,new}.txt
name      old time/op    new time/op    delta
Template     391ms ± 6%     385ms ± 6%    ~     (p=0.127 n=19+20)
GoTypes      1.27s ± 2%     1.27s ± 2%    ~     (p=0.172 n=19+19)
Compiler     6.17s ± 2%     6.15s ± 2%    ~     (p=0.647 n=19+20)

name      old alloc/op   new alloc/op   delta
Template    63.7MB ± 0%    63.4MB ± 0%  -0.35%  (p=0.000 n=16+20)
GoTypes      219MB ± 0%     218MB ± 0%  -0.38%  (p=0.000 n=20+20)
Compiler     980MB ± 0%     976MB ± 0%  -0.38%  (p=0.000 n=20+20)

name      old allocs/op  new allocs/op  delta
Template      586k ± 0%      584k ± 0%  -0.30%  (p=0.000 n=20+20)
GoTypes      1.80M ± 0%     1.79M ± 0%  -0.31%  (p=0.000 n=20+20)
Compiler     7.74M ± 0%     7.71M ± 0%  -0.34%  (p=0.000 n=20+20)

Change-Id: Ie21a5443c33a23ce30f987bdddec9fe350365d35
Reviewed-on: https://go-review.googlesource.com/21017Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This is follow-up 3 of 3 to CL 20959.

Passes toolstash -cmp.

Change-Id: I06efded21bbc970cbefa10e8f2cac1ebc6942e1b
Reviewed-on: https://go-review.googlesource.com/21054
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This is follow-up 1 of 3 to CL 20959.

Passes toolstash -cmp.

Change-Id: I9bddf7d88333fa4755e03ff8a034a35bd01b7855
Reviewed-on: https://go-review.googlesource.com/21052
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #14199

Change-Id: Ic9284023b663de3db1ca7b7b1e96eeab82ec0944
Reviewed-on: https://go-review.googlesource.com/21016
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

This commit replaces some of

for i := len(x) - 1; i >= 0; i-- {...}

style loops, which do not rely on reverse iteration order.

Change-Id: I5542834286562da058200c06e7a173b13760e54d
Reviewed-on: https://go-review.googlesource.com/21044Reviewed-by: Keith Randall <khr@golang.org>